All Questions
7
questions
2
votes
0
answers
34
views
Generating Functional for Massless Spin 2 Particle
I'm trying to derive the generating functional for a massless, spin 2 field. However, I am getting a left over term that needs to go away. I'm working in de Donder gauge so that $\partial_\mu h^{\mu\...
- 41
1
vote
0
answers
88
views
Path integral of Quantum Gravity while keeping Einstein's relation satisfied
Suppose we have a field $\phi(x)$ and the metric field is $g_{\mu \nu}(x)$. The action is the functional $S[\phi (x) , g_{\mu \nu } (x)] $. We want to do the path integral:
$$\int d[\phi (x)] d[g_{\mu ...
- 6,355
3
votes
1
answer
193
views
Regularization of $\delta$ function and Chiral anomaly in gravity
Mark Srednicki's QFT book presents a regularization of the $\delta$ function in calculating the chiral anomaly (see section 77 of the book). This regularization reads
\begin{equation}
\delta (x-y)=\...
- 995
2
votes
1
answer
704
views
Main idea behind this paper on Closed-time-path functional formalism
I tried to understand following paper: Closed-time-path functional formalism in curved spacetime: Application to cosmological back-reaction problems but I can't understand what is going on because I ...
- 3,043
16
votes
2
answers
424
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On the finiteness of quantum gravity$.$
Consider naïve quantum gravity, defined by
$$
Z=\int e^{-\frac{1}{\hbar}\int R}\mathrm dg
$$
where $R$ denotes the Ricci scalar, and $\mathrm dg$ a path integral over all metrics. I have set $G_N=1$ ...
8
votes
0
answers
383
views
Definition of gravity path integral?
In a non-abelian gauge theory there is a "fundamental" gauge field $A_\mu^a$ with gauge index $a$ often called connection. Although $ A_\mu^a$ is not gauge invariant, gauge invariant quantities can be ...
- 322
8
votes
3
answers
2k
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What happens when you apply the path integral to the Einstein-Hilbert action?
The Einstein Field Equations emerge when applying the principle of least action to the Einstein-Hilbert action, and from what I understand the path integral formulation generalizes the principle of ...
- 453